Added private projects.

It is now possible to create private projects. To mark a project as
private, you simply go in the Administer > Tabs Access menu and select
"Private project". Only project members and owners together with the
extra authorized users will be able to access the project. The project
will not appear in the list of projects for not authorized users.

src/IDF/Precondition.php

@@ -23,6 +23,26 @@
 
 class IDF_Precondition
 {
+    /**
+     * Check if the user has a base authorization to access a given
+     * tab. This used in the case of private project. You need to
+     * further control with the accessSource, accessIssues,
+     * etc. preconditions.
+     *
+     * @param Pluf_HTTP_Request
+     * @return mixed
+     */
+    static public function baseAccess($request)
+    {
+        if (!$request->project->private) {
+            return true;
+        }
+        if ($request->user->hasPerm('IDF.project-authorized-user', $request->project)) {
+            return true;
+        }
+        return self::projectMemberOrOwner($request);
+    }
+
     /**
      * Check if the user is project owner.
      *
@@ -98,16 +118,28 @@ class IDF_Precondition
 
     static public function accessSource($request)
     {
+        $res = self::baseAccess($request);
+        if (true !== $res) {
+            return $res;
+        }
         return self::accessTabGeneric($request, 'source_access_rights');
     }
 
     static public function accessIssues($request)
     {
+        $res = self::baseAccess($request);
+        if (true !== $res) {
+            return $res;
+        }
         return self::accessTabGeneric($request, 'issues_access_rights');
     }
 
     static public function accessDownloads($request)
     {
+        $res = self::baseAccess($request);
+        if (true !== $res) {
+            return $res;
+        }
         return self::accessTabGeneric($request, 'downloads_access_rights');
     }
 }